The mini filter knobs up top control a second, HP, filter in series with the LP, just as on the CS80, I assume. Unfortunately, it doesn’t appear that the HP filter is voltage controllable on the Boomstar 🙁

Just bought an Omega 8. The Omega and CODE come with Oberheim and Minimoog filters built-in. Can upgrade to CS-80, 303 and Arp 2600 filters on each individual voice. Around $140 per voice, so more than 1k to add additional filters for all 8. Room for 4 filters total, I think. I will get all 8x CS-80 filters when I can afford it.

I spent hours searching YouTube for info about the eurorack modules w Pittsburgh modular – nova musik had the best interview about them. The 4075 5089 3003 and a vca are in production with other filters coming. They are coming “in the fall” and designed to bring a boomstar to your eurorack.